The invention relates to a plastic well pipe comprising a perforated wall.
Plastic well pipes, which are used at great depths for recovering fluids, e.g. water or oil, are known.
A plastic well pipe is known, for example, which consists of a thermosetting resin re-inforced with glass filaments, the wall of said plastic well pipe comprising slots for the passage of water or oil. This plastic well pipe is disadvantageous, in virtue of the fact that reinforcing filaments are cut through when slots are formed in the wall of the pipe, thus causing a decrease in the strength of the pipe. This is particularly disadvantageous as these plastic well pipes are used at great depths where high strength properties are required so that the pipes are resistant to the pressures at those great depths.
In order to prevent a decrease in the properties of strength of such plastic well pipe, it has been suggested to wind the reinforcing filaments, in the form of glass filaments, in predetermined directions and to form the slots so that cutting through glass filaments occurs as little as possible. This pipe has the disadvantage that the manufacture requires much labor expenditure because the step of forming the slots in a predetermined direction, can only be performed by skilled laborers.
There is also known a plastic well pipe of thermoplastic, comprising slots or bores in the wall, but this pipe presents the disadvantage that the wall thickness of these plastic well pipes is very important in order to meet the strength requirements. This involves the use of a large amount of plastics, and the great weight of such pipes makes the handling of the pipes and the installation for recovering liquids, such as water or oil, extremely labor expensive.